Ehret hypothesizes an origin in Proto-Afroasiatic*bǔ(“place”) and compares Arabicبِـ (bi-, “in, with, by”); as with other attempts at reconstructing Proto-Afroasiatic, academic consensus is lacking.
Related to (and probably developed from) earlier nj(“not”).[1] The spelling with b- may reflect a graphic phenomenon rather than a sound change. Compare the Late Egyptian development of bn from Earlier Egyptian nn.
The verb used with bw in forming the negative aorist is usually periphrastic jrj, which is then followed by the main verb in the infinitive; however, when the main verb is rḫ or when the text belongs to a high linguistic register, periphrastic jrj is often not used and the main verb is directly negated instead. In forming the ‘not yet’ construction, periphrastic jrj is usually used, but especially with verbs of motion the main verb is sometimes directly negated instead. Periphrastic jrj is not used in forming the negative preterite.
“bw (lemma ID 55110)”, in Thesaurus Linguae Aegyptiae[2], Corpus issue 17, Web app version 2.01, Tonio Sebastian Richter & Daniel A. Werning by order of the Berlin-Brandenburgische Akademie der Wissenschaften and Hans-Werner Fischer-Elfert & Peter Dils by order of the Sächsische Akademie der Wissenschaften zu Leipzig, 2004–15 December 2022
“bw (lemma ID 55130)”, in Thesaurus Linguae Aegyptiae[3], Corpus issue 17, Web app version 2.01, Tonio Sebastian Richter & Daniel A. Werning by order of the Berlin-Brandenburgische Akademie der Wissenschaften and Hans-Werner Fischer-Elfert & Peter Dils by order of the Sächsische Akademie der Wissenschaften zu Leipzig, 2004–15 December 2022
James P[eter] Allen (2010) Middle Egyptian: An Introduction to the Language and Culture of Hieroglyphs, 2nd edition, Cambridge: Cambridge University Press, →ISBN, page 84, 92, 261.
Junge, Friedrich (2005) Late Egyptian Grammar: An Introduction, second English edition, Oxford: Griffith Institute, page 100–101, 153
^ Oréal, Elsa (2022) “The negative existential cycle in Ancient Egyptian” in Ljuba Veselinova & Arja Hamari (eds.), The Negative Existential Cycle, Berlin: Language Science Press, pages 197–230